Someone must have seen their faces.

If not a witness, maybe a security camera or cellphone video might emerge to help police find four suspects who left a Southern California man in critical condition in an Atlanta hospital.

Mark Calub was one of three men viciously attacked in Atlanta on April 22. It was the first time he had ever visited the city, friend Jessica Roache said.

He’s still in critical condition and his San Francisco-based family has to travel back and forth to monitor Calub’s progress, Roache said.

They are raising money to help with medical costs via YouCaring.

“Mark is a well-loved brother, son and friend to so many, and we are beyond devastated by this tragedy,” the family says on the fundraising website.

The attack was not only extreme but also entirely random, Roache told The Atlanta Journal-Constitution on Monday.

“They didn’t even take their stuff,” she said.

Now Roache, Calub’s Atlanta friends and his out-of-state friends are praying the case doesn’t go cold and someone brings a tip to police.

Roache helped set up a Facebook Page to spread the news of what happened to Calub.

She’s also hoping someone — either a nearby business with surveillance footage or a witness who recorded the attack on a cellphone — might come forward to help identify the suspects.

Three of the four people who assaulted Calub and his friends were seen from behind, running down Edgewood Avenue about 3:16 a.m. the night of the attack.

“It was late at night, but I think there were other people in the area and they might have a better memory of these guys’ faces,” Roache said.

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